Other Parts Discussed in Thread: TPS65982, TPS65987D
. Table 6 in the TPS65981 datasheet shows that all of the current sensing values have a divider ratio of N/A. However, Page 15 lists various A/V accuracies for the current sensing circuitry. These values seem to be giving the divider ratio that would accurately convert the raw ADC reading to the value in Amps. In the TPS65981 Application Customization software, I can read the ADC values and it seems like it is basing its values off of the dividers in the hi_functions.py script. These numbers don’t always match the values from the datasheet on page 15. For example, IPP_HV in the script defines a divider ratio of 3, but the datasheet accuracy lists 5. IPP_CABLE lists a divider ratio of 0.7 but the datasheet accuracy lists 1.0.
My personal testing indicates that the values given on the datasheet page 15 are accurate by stepping through various loads on each of the relevant power rails. The values being reported by the TPS65981 Application Customization software seems to be underreporting due to the 3/5 and 0.7/1.0 discrepancy between the datasheet and the code.
I was hoping you could confirm what the proper divider ratios should be for the different current readings, and I’d also like to understand why the divider ratios are listed as N/A in Table 6. Are they configurable somewhere?
From Pg.15:
